KR20160038438A - Release film and manufacturing method thereof - Google Patents

Abstract

The present invention relates to a release film. More specifically, the present invention relates to an in-line coating release film which is excellent in evenness and is used in electronic materials for multi layer ceramic condensers (MLCCs), prevention of polarizing plates, and optical clear adhesives (OCAs); and relates to an in-line coating release film used in window films. To this end, a release coating layer is formed on one side or both sides of a polyester base material film.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a release film,

The present invention relates to a release film. More particularly, to an in-line coating release film applied to a window or an electronic material.

Polyester film is excellent in physical stability and chemical resistance in a wide temperature range, and has good mechanical strength, surface characteristics and thickness uniformity, and can be applied to various applications and process conditions. Accordingly, the demand is increasing in response to the trend of high speed and automation in recent years, for example, for capacitors, photographic films, labels, pressure sensitive tapes, decorative laminates, transfer tapes, polarizing plates and ceramics.

Among them, silicone-coated release films are being converted from off-line coating to in-line coating release films in order to reduce cost.

In the in-line coating release film, when the roughness is low due to the nature of the release coating layer, a blocking phenomenon occurs due to an air gap disappearing between the film and the film. Therefore, a process loss may occur, and a change in physical properties depending on a coating type may occur. When the acrylic coating is applied, the release coating layer and the acrylic coating layer react with each other to cause a lock-up phenomenon. When the polyurethane or the ester compound is coated, post-curing of the release coating layer is not achieved due to the catalyst poison.

SUMMARY OF THE INVENTION The present invention has been conceived to solve the problems as described above, and it is an object of the present invention to provide an in-line coating method which is excellent in smoothness and used for electronic materials such as a multilayer ceramic capacitor (MLCC) It is an object of the present invention to provide an in-line coating release film used for a release film and a window film.

It is another object of the present invention to provide a release film which solves the non-uniformity of the release coating layer which occurs during coating by the in-line coating method, realizes low surface roughness and transparency, and does not generate windability and fish eyes.

In addition, the present invention relates to a polyester film having a maximum acid height surface roughness (Rp) of 0.3 mu m or less at one surface (surface A) of the film, preferably 0.1 mu m to 0.3 mu m, Film.

The present invention also provides a release film comprising the polyester film as a base film and having a release coating layer formed on one side or both sides thereof. The release film is excellent in adhesion to the polyester film, has little change in releasing force with time, To provide a release film having a small deviation and a high residual adhesion ratio.

The present invention also provides a release film in which the thickness of the polyester base film is in the range of 10 to 75 μm, and the thickness of the release layer is also 0.07 to 0.3 μm so that the film can be coated with the thin film. And a method for producing a release film using the same.

In order to achieve the above object,

The present invention relates to a polyester base film, wherein a release coating layer is formed on one side or both sides of the polyester base film, the release coating layer comprising at least one of the following compounds of the following general formulas (1) and (2) And a release film.

Pa? 0.6 (Equation 1)

Dmax? 2.5 (Equation 2)

(In the above equations (1) and (2), Pa is the average particle diameter of the particles (mu m) and Dmax is the maximum particle diameter of the particles (mu m).

[Chemical Formula 1]

(Wherein n, m, a and b are from 3 to 100).

(2)

(Wherein n is from 20 to 3000, m is from 1 to 50, and a is from 3 to 100).

(3)

(Wherein a is from 1 to 150, b is from 3 to 300, and a + b is from 5 to 300).

In addition,

a) melt-extruding a polyester resin to prepare a sheet;

Pa? 0.6 (Equation 1)

Dmax? 2.5 (Equation 2)

(In the above formulas 1 and 2, Pa represents an average particle diameter (占 퐉) of a particle and Dmax represents a maximum particle diameter (占 퐉) of a particle.

b) stretching the sheet 3 to 5 times in the machine direction at 80 to 150 ° C;

c) a polyester base film which is uniaxially stretched in the longitudinal direction, at least one of the following compounds of the following general formulas (1) and (2) and a compound of the general formula (3) and a platinum catalyst and a second particle are contained Lt; RTI ID = 0.0 > a < / RTI > release coating composition;

d) drying the film coated with the releasing coating composition at 130 to 150 캜 and preheating, and then stretching the film in a transverse direction by 3 to 4 times to prepare a releasing film having a releasing coating layer; And

e) heat treating;

The present invention also provides a method for producing a release film.

[Chemical Formula 1]

(Wherein n, m, a and b are from 3 to 100).

(2)

(Wherein n is from 20 to 3000, m is from 1 to 50, and a is from 3 to 100).

(3)

(Wherein a is from 1 to 150, b is from 3 to 300, and a + b is from 5 to 300).

The release film according to the present invention effectively controls the maximum particle diameter (Dmax) with respect to the average particle diameter and the particle size distribution of the base film and the release-coated particles, thereby satisfying the surface characteristics that the release film for window or electronic material should basically have And at the same time an excellent smoothness can be realized. In addition, the proper surface roughness can be controlled to ensure winding and workability, and the generation of pinholes can be effectively controlled by reducing fish eyes.

In addition, the release film according to the present invention is suitable for use in a window or an electronic material without causing blocking even when the surface of the release layer is flat and rolled up into a roll.

In addition, the release film according to the present invention can be coated with an in-line coating method to reduce loss caused by post-processing, and it is possible to reduce the manufacturing cost, thereby maximizing economical efficiency and productivity due to cost reduction.

Further, there is an advantage that a uniform coating layer is formed, the change of the releasing force over time and the variation thereof are small, and the releasability with a residual sticking ratio of 90% or more can be realized.

1 is a graph showing the position of the maximum particle diameter in the present invention.

Hereinafter, each configuration of the present invention will be described in more detail.

The present invention relates to low-light, highly transparent electronic materials or release films for windows.

In one embodiment of the present invention, the substrate film is a polyester base film containing a first particle satisfying the following formulas 1 and 2, or using a polyester alone resin.

Pa? 0.6 (Equation 1)

Dmax? 2.0 (Equation 2)

(In the above equations (1) and (2), Pa is the average particle diameter of the particles (mu m) and Dmax is the maximum particle diameter of the particles (mu m).

At this time, the first particles may be added at the time of synthesizing the polyester resin, or may be mixed at the melt extrusion step after synthesis of the polyester resin, but are not limited thereto. Preferably, the dispersibility of the particles is excellent. In order to prevent agglomeration between the particles, it is preferable to mix the particles and glycol in the slurry state during polymerization of the polyester resin.

In one embodiment of the present invention, the average particle diameter of the first particles is 0.6 mu m or less, preferably 0.15 to 0.6 mu m. The maximum particle diameter of the first particles is 2.0 占 퐉 or less, preferably 0.6 to 2.0 占 퐉. When the above range is satisfied, the polyester base film is excellent in surface smoothness and has a good surface.

When the maximum particle diameter of the first particles is more than 2.5 탆, the running property and the winding property are good, but the presence of coarse particles increases the probability of occurrence of defects in the production of the polyester base film, The orange peel phenomenon can occur when the film surface looks rugged like an orange peel. This causes coating unevenness in a post-process, and may be transferred to a coated adhesive or the like to cause defects.

In the present invention, the maximum particle diameter (탆) of the particles is measured using a particle size distribution meter. In this case, the particle size of the large particles in the particle size distribution graph means the size of the particles remaining before the volume becomes 0%.

Fig. 1 is a graph showing the particle size distribution of inorganic particles mainly used. Dmax in Fig. 1 means maximum particle diameter (占 퐉).

In one embodiment of the present invention, the content of the first particles is preferably 0.25% by weight or less based on the total weight of the film. In the case of using more than 0.25 wt%, the maximum peak height surface roughness (Rp) increases and pinholes are generated or the possibility of fish-eye due to particle agglomeration is increased.

In an embodiment of the present invention, the difference in size between the average particle diameter and the maximum particle diameter of the first particles is not limited, but the smaller the difference in size, the more uniform smoothness can be achieved. Preferably, as can be seen from the particle size distribution graph, the maximum peak height surface roughness (Rp) of the narrower graph including a large amount of uniform particles is reduced, and the occurrence of pinholes can be suppressed. The first particles have the best smoothness in a range of a correlation (Pa / Dmax) between an average particle diameter and a maximum particle diameter of preferably 0.1 to 0.4, more preferably 0.2 to 0.38.

In one embodiment of the present invention, the method of incorporating the polyester into the polyester base film of the first particle is not limited, but it is preferable to add the polyester base film in the form of a slurry dispersed in glycol during the synthesis of the polyester resin, It is preferable since aggregation can be prevented.

In one embodiment, the polyester may be obtained by condensation polymerization of an acid component containing a dicarboxylic acid as a main component and a glycol component containing an alkyl glycol as a main component, and the particles may be added in the condensation polymerization step or the solid phase polymerization step, It is preferable to add the slurry in the form of a slurry dispersed in the glycol component when the particles are added.

In one embodiment of the present invention, the polyester resin constituting the polyester base film may be a resin obtained by condensation polymerization of an acid component containing a dicarboxylic acid as a main component and a glycol component containing an alkyl glycol as a main component. As the main component of the dicarboxylic acid, terephthalic acid or an alkyl ester thereof or a phenyl ester thereof is mainly used, but a part of the dicarboxylic acid is used as a main component of the dicarboxylic acid such as isophthalic acid, oxyethoxybenzoic acid, adipic acid, sebacic acid, 5-sodium sulfoisophthalic acid Can be used in place of the bifunctional carboxylic acid or an ester-forming derivative thereof. The glycol component is mainly ethylene glycol, but a part of the glycol component is exemplified by propylene glycol, trimethylene glycol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, 1,4-bisoxyethoxy Benzene, bisphenol, and polyoxyethylene glycol. Alternatively, a monofunctional compound or a trifunctional compound may be used in combination if the content is small.

In one embodiment of the present invention, the first particles are not particularly limited as long as the average particle diameter, the addition amount, and the size distribution are within the range of the present invention, but preferably the average particle diameter is 0.15 to 0.6 탆, The content is 0.25 wt% or less, and the maximum particle size (Dmax) in the particle size distribution is 0.6 to 2.0 mu m.

In one embodiment of the present invention, the kind of the first particles is not limited, and may be inorganic particles, organic particles, or a mixture of inorganic particles and organic particles, and one or a mixture of two or more kinds may be used. That is, it is also possible to use one kind or two or more types of inorganic particles, use one kind or two or more kinds of organic particles, or use one kind or two kinds or more kinds of inorganic particles and one kind or two kinds or more kinds of organic particles Do.

Specific examples of the inorganic particles include calcium carbonate, titanium oxide, silica, kaolin, and barium sulfate. The organic particles may be selected from silicone resin, crosslinked divinylbenzene polymethacrylate, crosslinked polymethacrylate, crosslinked polystyrene resin, Benzoguanamine-formaldehyde resin, benzoguanamine-melamine-formaldehyde resin, and melamine-formaldehyde resin.

In one embodiment of the present invention, the polyester base film may have a haze of 0.3-10%. When the haze of the film is less than 0.3%, although transparency is excellent, scratches tend to occur during the film forming process, and roll pressing marks may occur in the MD stretching section, resulting in poor appearance. When the haze is more than 10%, the transparency is low, which may interfere with the inspection of defective portions such as pinholes and defects which are usually performed in an electronic material film.

In one embodiment of the present invention, the polyester base film has a maximum acid height surface roughness (Rp) of 0.1 to 0.3 mu m.

The surface roughness Rp of the maximum peak height was measured using a two-dimensional surface roughness meter (Kosaka Lab. Surfcorder SE-3300) based on JIS B0601 at a measurement speed of 0.05 mm / sec, a stylus radius of 2 탆, , The cutoff value is 0.08 mm, and the reference length of 1.5 mm is selected from the curved line of the film cross section in the direction of the center line thereof, and the total of five times is measured, and the average value is calculated. At this time, the highest profile mountain height from the center line in the sampling length is the maximum mountain height surface roughness Rp.

If the maximum peak height Rp is less than 0.1 占 퐉, there is a side effect that the haze of the film is reduced but the surface projection is small to increase the coefficient of friction to decrease the releasability. If the maximum peak height surface roughness Rp is more than 0.3 占 퐉, Due to the increase of the surface protrusion due to the particles, orange peel occurs when used as a release film for electronic materials, or may be detected as foreign matter during the inspection of the final product. Therefore, the polyester base film according to the present invention has a maximum peak height surface roughness Rp of 0.3 mu m or less, and preferably has a maximum peak height surface roughness Rp of 0.15 to 0.27 mu m.

In one aspect of the present invention, the polyester base film may have a static friction coefficient and a dynamic friction coefficient of 0.2 to 0.7. When the coefficient of static friction and the coefficient of dynamic friction are more than 0.7, the winding property is poor and protrusion occurs and scratches are generated. If it is less than 0.2, there is a high possibility that the slip property of the film increases and the foam slip occurs.

In order to improve the smoothness of a polyester base film having a low surface roughness and to improve the problem that the spin-off property is bad and the fish-eye is generated or the coating layer is uneven when coating the release coating composition, The release coating composition comprises at least one of the following compounds of the following general formulas (1) and (2), the compound of the general formula (3), the platinum catalyst and the second particle.

[Chemical Formula 1]

(Wherein n, m, a and b are from 3 to 100).

(2)

(Wherein n is from 20 to 3000, m is from 1 to 50, and a is from 3 to 100).

(3)

(Wherein a is from 1 to 150, b is from 3 to 300, and a + b is from 5 to 300).

(1) and (2) are in a prepolymer state as a main theme of the release coating layer, and the formula (3) reacts with the above formula (1) or (2) as a cure. That is, the vinyl group of formula (1) or (2) reacts with the silane group of formula (3). In the above formula (3), the silane group (Si-H) and Si-CH3 are randomly crossed, so that the steric hindrance is lower than the curing agent in which only the silane group is continuous.

Commercial examples of Formula 1 include EM490 from Wacker, 7920, 7934 from Dow Corning, and the like.

Commercial examples of the above formula (2) include 3951 of Shin-Etsu, D400E of Wacker, and the like.

Commercial examples of the above formula (3) include V-72 and V-15 of Wacker, but the present invention is not limited thereto.

The release coating layer may include, but is not limited to, at least one selected from the compounds represented by Formulas 1 and 2, a compound represented by Formula 3, a platinum-based catalyst, and a second particle, and has a solid content of 10 to 30% A phosphorus-type coating composition may be formed by coating to a thickness of 0.07 to 0.3 탆.

If the solid content is less than 10 wt%, the surface of the polyester film can not be sufficientlycoated to cause a deviation in releasing force. If the solid content exceeds 30 wt%, the in-line coating can not supply sufficient heat, Can be lowered. When the coating thickness is less than 0.07 mu m, the high peaks of the polyester film are not covered with the coating layer and the releasing force is high. When the coating thickness is more than 0.3 mu m, the occurrence of coating unevenness and the reaction conversion ratio of the releasing coating layer may be lowered.

Commercial examples of the platinum-based catalysts include, but are not limited to, EM440 from Wacker.

The second particles are included in order to realize excellent transparency while lowering the surface roughness of the release coating layer. The kind of the second particles is not limited, but may be an inorganic particle, an organic particle, or a mixture of an inorganic particle and an organic particle, and one or a mixture of two or more kinds may be used. That is, it is also possible to use one kind or two or more types of inorganic particles, use one kind or two or more kinds of organic particles, or use one kind or two kinds or more kinds of inorganic particles and one kind or two kinds or more kinds of organic particles Do.

When the second particles are inorganic particles, any one or two or more selected from the group consisting of silica, alumina, zirconia and titania can be used. The average particle diameter of the second particles is not limited, but a coating layer suitable for use as a release film can be formed in a range of an average particle diameter of 10 to 1500 nm, more preferably 50 to 800 nm, and a coating layer is formed by an inline coating method It is preferable.

The second particles are preferably contained in the coating layer in an amount of 0.1 to 10% by weight, more preferably 0.1 to 5% by weight. If the content of the particles is less than 0.1% by weight, the surface roughness may be very low, resulting in poor winding and blocking problems. When the content of the particles is more than 10% by weight, haze may increase rapidly or grain aggregation may occur, ≪ / RTI >

In the present invention, it is more preferable that the second particles use organic particles with a small haze change rate, do not cause particle agglomeration, and do not affect the silicon reaction.

The second particle preferably satisfies the following formulas 3 and 4 to prevent blocking that may occur between the film and the film, and can realize excellent transparency.

0.01? Pa? 1.5 (3)

0.03? Dmax? 2.0 (Equation 4)

(In the above formulas 3 and 4, Pa is the average particle diameter of the particles (mu m) and Dmax is the maximum particle diameter of the particles (mu m).)

In the release coating layer of the present invention, the content of the second particles is not limited, but preferably 0.01 to 10% by weight, more preferably 0.1 to 0.5% by weight in the release coating layer.

In the present invention, the release coating layer may further comprise at least one component selected from the group consisting of an alcohol solvent, a wetting agent and a slip agent.

The alcohol-based solvent may be used for uniformly applying the wetting agent with increased wettability. As one specific example, a volatile fast-drying solvent such as isopropyl alcohol, N-propanol, ethyl cellosolve, methylcellosolve, or butyl cellosolve can be used, but is not limited thereto. In another embodiment, water may be used in place of the alcoholic solvent. The content of the alcoholic solvent is preferably 0.1 to 10% by weight in the release coating composition. If the content of the alcoholic solvent is less than 0.1%, the effect is insignificant. If the content of the alcoholic solvent is more than 10% It happens.

The wetting agent is used for uniformly spreading the emulsion on the polyester film, and any one or more selected from the group consisting of polyethylene glycol, polyethylene ester, modified silicone, and fluorine-based compounds can be used. The above-mentioned wetting agent is not limited, but a silicon-based wetting agent is preferred. Such silicone-based whitening agents include, for example, Q2-5212 of Dow Corning Corporation, Wet-250 of TEGO Corporation, and the like.

The content of the wetting agent is preferably 0.1 to 1.0 wt%, and when the content is less than 0.1 wt%, the effect is insignificant. When the content is 1.0 wt% or more, the wetting agent is likely to be transferred to an adhesive used in post-processing.

In one embodiment, the release coating composition may have a solids content of 5 to 25% by weight, more specifically 8 to 16% by weight, of the at least one component selected from the compounds of the formulas (1) and (2). If it is less than 5% by weight, the film surface can not be sufficiently covered. If it is more than 25% by weight, the reaction conversion rate is low and the residual sticking rate may be increased.

The solid content of the compound of Formula 3 may be 0.5 to 5 wt%, more specifically 0.8 to 2 wt%. If the amount is less than 0.5% by weight, the release coating layer can not be sufficiently cured. If the amount is more than 5% by weight, the unreacted silane group may increase the change in the releasing force over time. The solid content of the platinum-based catalyst may be 0.001 to 3 wt%, more specifically 0.005 to 0.1 wt%. If the amount is less than 0.001% by weight, the effect is insignificant. If the amount is more than 3% by weight, the Pt catalyst may remain in an excessive amount, resulting in unevenness in releasing force. The solid content of the wetting agent may be 0.1 to 3 wt%, more specifically 0.5 to 2 wt%. If it is less than 0.1% by weight, the effect is insignificant, and if it is more than 3% by weight, coating unevenness may be caused.

The release film according to the present invention is a release film obtained by maintaining the adhesive tape in an adhered state at 70 DEG C for 24 hours, removing the adhesive tape, lapping it on a Teflon sheet, Lt; / RTI >

Residual Adhesion Rate = Adhesion of adhesive tape after aging for 24 hours at 70 占 폚 / Adhesion of initial adhesive tape 占 100 (Equation 5)

It is possible to judge that the unreacted materials of the release film are low in the range of the residual adhesion ratio of 90% or more, so that the amount of unreacted materials of the release film after the post-processing is transferred to the final product by the customer is small.

In order to obtain such a polyester film, a method for producing a polyester film according to an embodiment of the present invention comprises

a) preparing a sheet by melt-extruding a polyester resin comprising first particles satisfying the following formulas 1 and 2;

0.15? Pa? 0.6 (1)

0.6? Dmax? 2.5 (Equation 2)

(In the above Equations 1 to 3, Pa represents the average particle diameter (占 퐉) of the particles and Dmax represents the maximum particle diameter (占 퐉) of the particles.

b) stretching the sheet 3 to 5 times in the machine direction at 80 to 150 ° C;

c) a polyester base film which is uniaxially stretched in the longitudinal direction, at least one of the following compounds of the following general formulas (1) and (2) and a compound of the general formula (3) and a platinum catalyst and a second particle are contained Lt; RTI ID = 0.0 > a < / RTI > release coating composition;

d) drying the film coated with the releasing coating composition at 130 to 150 캜 and preheating, and then stretching the film in a transverse direction by 3 to 4 times to prepare a releasing film having a releasing coating layer; And

and e) heat treating.

In the manufacturing method of the present invention, the release coating composition may be applied using a gravure roll in step c).

The application method is not limited, but it is preferable to use a gravure coating roll because the release coating composition can be applied to a uniform thickness.

If the temperature is lower than 130 ° C, the film may be broken. If the temperature is higher than 155 ° C, the uniformity of the film thickness may be lowered. If the stretching ratio is less than 3 times, the film thickness uniformity may be lowered. If the stretching ratio is more than 4 times, the film may be broken.

In the step e), the heat treatment may be performed at 230 to 250 ° C. If the temperature is lower than 230 ° C, the release coating layer may not sufficiently react and may be pushed. When the temperature exceeds 250 ° C, heat wrinkling and orange peel may occur.

The release film may be a polyester base film having a thickness of 10 to 75 탆 and a release coating layer having a thickness of 0.07 to 0.3 탆.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the present invention is not limited to the following examples.

1) Measurement of average particle diameter and maximum particle diameter (Dmax) of particles:

The average particle diameter and the maximum particle diameter (Dmax) were measured using a particle size distribution analyzer (Beckman-Coulter, LS13 320). The size of the remaining particles immediately before the volume of large particles becomes 0% on the particle size graph is called the maximum particle diameter (Dmax). The graph of the particle size distribution is shown in Fig.

2) Haze measurement:

The measurement method was based on ASTM D-1003. Seven portions were randomly extracted from two locations on the edge of the polyester film, one at the center, and then cut into a size of 5 cm × 5 cm. A haze meter (NDH 300A, And light of 555 nm wavelength was transmitted, and the average value except the maximum / minimum value was calculated by the following formula.

Haze (%) = (total scattered light / total transmitted light) × 100

3) Surface roughness (Ra) and maximum peak height Surface roughness (Rp) measurement:

Measured under the conditions of a measurement speed of 0.05 mm / sec, a stylus radius of 2 탆, a load of 0.7 mN and a cutoff value of 0.08 mm using a two-dimensional surface roughness meter (Kosaka Lab. Surfcorder SE-3300) based on JIS B0601, (X) and the y-axis in the vertical direction, and the y = f (x) as the center line and the y-axis in the vertical direction, respectively. The following formula was obtained.

(L: 측정길이)

(L: measurement length)

At this time, the largest profile peak height from the center line in the sampling length was defined as the maximum peak height surface roughness (Rp).

4) Measurement of coating uniformity

If the area of the portion of the polyester releasing film where the release layer is not formed is less than 1% of the area of the base film, then it is indicated as "poor" if it exceeds 1%.

5) Coating thickness measurement

The silicon content of the release layer is measured with a calibrated XRF instrument (Oxford LX3500) and expressed in terms of coating thickness.

6) Measurement of releasing force (standard Tape: TESA 7475)

The tape was placed on the release coating layer and rubbed back and forth twice using 2 kg of rubber roll, and then cut into a size of 50 mm x 15 cm to prepare a sample. The prepared sample was allowed to stand at 55 DEG C for 24 hours under a load of 70 g / cm < 2 > and subjected to peel peel evaluation at 180 degrees using a Peel Tester (Chem Instrument, AR-1000).

The peeling speed was measured at a total of 5 times at a rate of 300 mm / min.

7) Measurement of the change of the release force over time

The tape was placed on the release coating layer and rubbed back and forth twice using 2 kg of rubber roll, and then cut into a size of 50 mm x 15 cm to prepare a sample. The prepared sample was allowed to stand at 55 DEG C for 240 hours under a load of 70 g / cm < 2 > and subjected to peel peel evaluation at 180 degrees using a Peel Tester (Chem Instrument, AR-1000).

The peeling speed was measured at a total of 5 times at a rate of 300 mm / min.

Average value of declining force change over time: Average value measured continuously over a range of 10cm.

Deformation force over time Deviation: Indicates the difference between the maximum and minimum values while continuously measuring the 10cm range.

8) Residual tack rate

As a method for confirming the transfer of the silicone release film to the adhesive after laminating the adhesive, the release film is laminated with an adhesive to induce transfer under severe conditions, and then the adhesive strength of the adhesive bonded to Teflon is evaluated in the same manner.

Generally, a residual tack rate of 90% or more is required.

In the following Examples and Comparative Examples, the particle and coating composition liquid were used as follows.

Particle A: Calcium carbonate particles having an average particle diameter of 0.59 mu m and a maximum particle diameter (mu m) of 2.2 mu m

Particle B: Titanium dioxide particles having an average particle diameter of 0.36 mu m and a maximum particle diameter (mu m) of 1.52 mu m

Particle C: Calcium carbonate particles having an average particle diameter of 0.51 mu m and a maximum particle diameter (mu m) of 2.42 mu m

Particle D: Silica particles having an average particle diameter of 0.19 mu m and a maximum particle diameter (mu m) of 0.6 mu m

Coating solution 1: 49.99% by weight of a polydimethylsiloxane (Dow Corning) 7920 of formula (1) in solid content, 0.01% by weight of solid content of a platinum catalyst (Wacker, EM440) and a total solids content of 50% by weight.

Coating solution 2: 49.99% by weight of polydimethylsiloxane (Shin-Etsu 3851) of formula 2 as a solid content, 0.01% by weight of solid content of a platinum catalyst (Wacker, EM440) and 50% by weight of total solids content.

Coating solution 3: A composition comprising 50% by weight of a hydrogen silane compound (Wacker, V-15) of formula (3) in solid content.

Coating solution 4: Silicone-based wetting agent (Dow Corning, Q2-5212) having a solids content of 80% by weight.

[Example 1]

So that a 20% by weight, and the coating liquid 2, the coating liquid 1 1.1% by weight, the coating solution 3 1.0 wt%, 80nm silica (SiO ₂₎ particles 0.15 The total solid content of 22.3% by weight of a mixture of weight percent and 800nm silica particles 0.05 wt% Water was added to prepare Coating Liquid A.

1000 g of dimethyl terephthalate, 576 g of ethylene glycol, 300 ppm of magnesium acetate as a polyester resin, and 400 ppm of trimethyl phosphate were introduced into the reactor and the ester exchange reaction was carried out while methanol was flowing out. After the transesterification reaction, the calcium carbonate particles A as shown in Table 1 were added in an amount of 1.0 part by weight based on 100 parts by weight of the polyester resin with ethylene glycol sludge (mixed with 50% by weight of calcium carbonate and 50% by weight of ethylene glycol) Respectively. Thereafter, condensation polymerization was carried out under a vacuum of 0.3 torr at 285 DEG C to obtain a polyester chip having an intrinsic viscosity of 0.61.

The polyester chips were melt-extruded at 280 DEG C and then quenched at 24 DEG C using a large-sized roll to obtain a polyester sheet. The obtained polyester sheet was stretched 3.5 times in the longitudinal direction at 110 DEG C and the coating liquid (A) was applied to the cooled film using a ceramic gravure coater.

After drying and preheating at 150 占 폚, the film was stretched 4 times in the transverse direction to prepare a biaxially stretched film. The obtained biaxially stretched film was heat-treated at 240 캜 to obtain a polyester film having a thickness of 25 탆.

The physical properties of the resulting polyester film were measured and are shown in Table 1 below.

[Examples 2 and 3]

The procedure of Example 1 was repeated to prepare polyester films having different particle types and contents as shown in Table 1 below.

The physical properties of the resulting polyester film were measured and are shown in Table 1 below.

[Example 4]

The procedure of Example 1 was repeated except that the particle D was used in the base film, the content in the film was as shown in Table 1, and the silica particles having an average particle diameter of 0.2 탆 were contained in the coating liquid A.

The physical properties of the resulting polyester film were measured and are shown in Table 1 below.

[Example 5]

The same procedure as in Example 1 was carried out except that a polyester single film not containing particles was used as the base film.

The physical properties of the resulting polyester film were measured and are shown in Table 1 below.

[Example 6]

Except that the particle A and the particle B were used in a mixture as shown in Table 1 below.

The physical properties of the resulting polyester film were measured and are shown in Table 1 below.

[Comparative Example 1]

The same procedure as in Example 5 was carried out except that the coating liquid A containing no silica particles was used.

The physical properties of the resulting polyester film were measured and are shown in Table 1 below.

[Comparative Example 2]

The same procedure as in Example 5 was carried out except that the coating liquid A containing no silica particles was used.

The physical properties of the resulting polyester film were measured and are shown in Table 1 below.

[Table 1]

Claims (20)

A release coating layer is formed on one side or both sides of the polyester base film,
Wherein the release coating layer comprises at least one of the following compounds of the following general formulas (1) and (2) and a compound of the general formula (3), a platinum catalyst and a second particle.
[Chemical Formula 1]

(Wherein n, m, a and b are from 3 to 100).
(2)

(Wherein n is from 20 to 3000, m is from 1 to 50, and a is from 3 to 100).
(3)

(Wherein a is from 1 to 150, b is from 3 to 300, and a + b is from 5 to 300). The method according to claim 1,
Wherein the polyester base film comprises first particles satisfying the following formulas (1) and (2).
Pa? 0.6 (Equation 1)
Dmax? 2.5 (Equation 2)
(In the above equations (1) and (2), Pa is the average particle diameter of the particles (mu m) and Dmax is the maximum particle diameter of the particles (mu m). The method according to claim 1,
And the second particle satisfies the following formulas (3) and (4).
0.01? Pa? 1.5 (3)
0.03? Dmax? 2.0 (Equation 4)
(In the above formulas 3 and 4, Pa is the average particle diameter of the particles (mu m) and Dmax is the maximum particle diameter of the particles (mu m).) The method according to claim 1,
Wherein the release coating layer further comprises at least one component selected from an alcohol solvent, a wetting agent and a slip agent. 3. The method of claim 2,
Wherein the release coating layer has a dry coating thickness of 0.07 to 0.3 mu m. The method according to claim 1,
Wherein the first particle and the second particle are an inorganic particle, an organic particle, or a mixture of an inorganic particle and an organic particle, wherein one or more of them are mixed. The method according to claim 1,
The content of the second particles is 0.1 to 10% by weight in the release coating layer 3. The method of claim 2,
Wherein the content of the first particles is 0.25% by weight or less based on the total weight of the film. The method according to claim 6,
Wherein the inorganic particles are at least one selected from the group consisting of calcium carbonate, alumina, titania, silica, barium sulfate, mica and kaolin, and the organic particles are at least one selected from the group consisting of silicone resin, crosslinked divinylbenzene polymethacrylate, Wherein the release film is at least one selected from the group consisting of a cross-linked polystyrene resin, a benzoguanamine-formaldehyde resin, a benzoguanamine-melamine-formaldehyde resin, and a melamine-formaldehyde resin. The method according to claim 1,
Wherein the polyester base film has a maximum peak height and a surface roughness (Rp) of 0.1 to 0.3 占 퐉. The method according to claim 1,
The polyester base film has a haze of 0.3 to 10%. The method according to claim 1,
Wherein the polyester base film has a thickness of 10 to 75 占 퐉. The method according to claim 1,
Wherein the releasing film is maintained at 70 DEG C for 24 hours in the state that the adhesive tape is adhered thereto, and then the adhesive tape is removed and lapped with a Teflon sheet, and the residual adhesive ratio calculated according to the following formula 6 is 90% or more.
Residual Adhesion Rate = Adhesion of adhesive tape after aging for 24 hours at 70 占 폚 / Adhesion of initial adhesive tape 占 100 (Equation 5) The method according to claim 1,
Wherein the release coating layer is formed by applying an in-line coating method. a) melt-extruding a polyester resin to prepare a sheet,
b) stretching the sheet 3 to 5 times in the machine direction at 80 to 150 ° C;
c) a polyester base film which is uniaxially stretched in the longitudinal direction, at least one of the following compounds of the following general formulas (1) and (2) and a compound of the general formula (3) and a platinum catalyst and a second particle are contained Lt; RTI ID = 0.0 > a < / RTI > release coating composition;
d) drying the film coated with the releasing coating composition at 130 to 150 캜 and preheating, and then stretching the film in a transverse direction by 3 to 4 times to prepare a releasing film having a releasing coating layer; And
e) heat treating;
Wherein the release film is formed by a method comprising the steps of:
[Chemical Formula 1]

(Wherein n, m, a and b are from 3 to 100).
(2)

(Wherein n is from 20 to 3000, m is from 1 to 50, and a is from 3 to 100).
(3)

(Wherein a is from 1 to 150, b is from 3 to 300, and a + b is from 5 to 300). 16. The method of claim 15,
Wherein the step of preparing the sheet is a step of melt-extruding a polyester resin containing first particles satisfying the following formulas (1) and (2).
0.15? Pa? 0.6 (1)
0.6? Dmax? 2.5 (Equation 2)
(In the above Equations 1 to 3, Pa represents the average particle diameter (占 퐉) of the particles and Dmax represents the maximum particle diameter (占 퐉) of the particles. 16. The method of claim 15,
Wherein the second particle satisfies the following formulas (3) and (4).
0.01? Pa? 1.5 (3)
0.03? Dmax? 2.0 (Equation 4)
(In the above formulas 3 and 4, Pa is the average particle diameter of the particles (mu m) and Dmax is the maximum particle diameter of the particles (mu m).) 16. The method of claim 15,
Wherein the release coating composition is applied using a gravure roll in the step c). 16. The method of claim 15,
Wherein the release film is a polyester base film having a thickness of 10 to 75 占 퐉 and the release coating layer has a dry coating thickness of 0.07 to 0.3 占 퐉. 16. The method of claim 15,
In the step (e), the heat treatment is performed at 230 to 250 ° C.

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